Abstract

Swift-heavy-ion irradiation creates latent tracks in SiO2glass and nanopores with a high aspect ratio can be formed along these ion paths by selective etching of the latent tracks using hydrogen fluoride (HF) vapor. Here we report that the size of nanopores can easily be controlled by simply changing the temperature of the HF solution generating the vapor and/or that of the SiO2glass exposed to the vapor. Furthermore, this method of size control was used to produce SiO2glass sheets with nanopores of different sizes and number densities for use as the waveguide layer in the sensing plates for a waveguide-mode sensor. In comparison with nonperforated plates, the increased surface area due to the formation of nanopores was found to create up to a tenfold increase in sensitivity.

Received 09 March 2011Accepted 19 June 2011Published online 27 July 2011

Acknowledgments:

The authors express their thanks to the Advanced Functional Materials Research Center of Shin-Etsu Chemical Co. Ltd. for supplying the SOQ substrates. Part of this work was conducted at the AIST Nano-Processing Facility, which is supported by “Nanotechnology Network Japan” of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. The present research was also financially supported by Industrial Technology Research Grant Program in 2009 from New Energy and Industrial Technology Development Organization, Japan (NEDO).